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Why change the spider's position?

This change is position is necessary to prevent the same ladybug from registering a collision with the same spider during the next iteration of thegame loop. The forward movement of the spiders and the ladybugs each time they move is less than the dimensions of the intersecting rectangles. Therefore,without a purposeful shift in position of either the ladybug or the spider, the pair would continue to register collisions until the rectangles finally separatefrom one another.

Spiders don't die easily

As you read in the Preview section, if a black widow spider collides with a ladybug, it simply moves 128 pixels tothe right and changes into a green spider. If a green spider collides with a ladybug, it simply moves 128 pixels to the right and changes into a brownspider. Finally, if a brown spider collides with a ladybug, it is eaten and removed from the population of spiders. This is accomplished by the code in Listing 12 .

Listing 12 . Spiders don't die easily.

//If the collision was with a black widow // spider, cause it to reincarnate into a// green spider. if(target.Image.Name == "blackWidowSpider") {target.SetImage("greenspider",Content); }//If the collision was with a green spider, // cause it to reincarnate into a brown// spider. else if(target.Image.Name == "greenspider") {target.SetImage("brownSpider",Content); }//If the collision was with a brown spider, // it gets eaten. Remove it from the list of// spiders. else if(target.Image.Name == "brownSpider") {spiders.Remove(target); }// end else-if}//end if }//end for loopbase.Update(gameTime); }//end Update method

The code in Listing 12 is relatively straightforward.

The Name property

The first statement in Listing 12 shows why I needed to set an identifiable string value into the Name property of the Texture2D object referred to by image in Listing 2 and Listing 3 . I needed a way to determine the type of spider involved in each collision so that I could take the appropriate action when acollision was detected.

Killing the brown spider

The call to the spiders.Remove method in Listing 12 removes the target Sprite object's reference from the list of spiders. Since this is the only reference to the Sprite object, this action should make the memory occupied by the Sprite object eligible for garbage collection.

Is a Dispose Method needed?

However, I'm not certain that garbage collection is sufficient to free up all of the resources owned by the now defunct object and its image. It might also beadvisable to use a Dispose Method . At the time I am writing this, I simply don't know.

The end of the Update method

Listing 12 also signals the end of the overridden Update method.

The overridden Game.Draw method

The overridden Game.Draw method is shown in its entirety in Listing 13 .

Listing 13 . The overridden Game.Draw method.

protected override void Draw(GameTime gameTime) { spriteBatch.Begin();spiderWeb.Draw(spriteBatch);//draw background //Draw all spiders.for(int cnt = 0;cnt<spiders.Count;cnt++) { spiders[cnt].Draw(spriteBatch); }//end for loop//Draw all ladybugs. for(int cnt = 0;cnt<ladybugs.Count;cnt++) { ladybugs[cnt].Draw(spriteBatch); }//end for loopspriteBatch.End(); base.Draw(gameTime);}//end Draw method //-------------------------------------------------//}//end class }//end namespace

Questions & Answers

Discuss the differences between taste and flavor, including how other sensory inputs contribute to our  perception of flavor.
John Reply
taste refers to your understanding of the flavor . while flavor one The other hand is refers to sort of just a blend things.
Faith
While taste primarily relies on our taste buds, flavor involves a complex interplay between taste and aroma
Kamara
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Ummi Reply
omeprazole
Kamara
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Renee
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Renee
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Kamara
Omeprazole Cimetidine / Tagament For the complicated once ulcer - kit
Patrick
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Nency Reply
Not really sure
Eli
to drain extracellular fluid all over the body.
asegid
The lymphatic system plays several crucial roles in the human body, functioning as a key component of the immune system and contributing to the maintenance of fluid balance. Its main functions include: 1. Immune Response: The lymphatic system produces and transports lymphocytes, which are a type of
asegid
to transport fluids fats proteins and lymphocytes to the blood stream as lymph
Adama
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Oyindarmola Reply
Anatomy is the identification and description of the structures of living things
Kamara
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Oyerinde Reply
Anatomy is the study of the structure of the body, while physiology is the study of the function of the body. Anatomy looks at the body's organs and systems, while physiology looks at how those organs and systems work together to keep the body functioning.
AI-Robot
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Mohammed Reply
Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems
Kamara
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Prince
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Wulku Reply
little girl okay how does the stomach protect itself from the damaging effect of HCL
Wulku
it is because of the enzyme that the stomach produce that help the stomach from the damaging effect of HCL
Kamara
function of digestive system
Ali Reply
function of digestive
Ali
the diagram of the lungs
Adaeze Reply
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Diya Reply
37 degrees selcius
Xolo
37°c
Stephanie
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Mark
36.5
Simon
37°c
Iyogho
the normal temperature is 37°c or 98.6 °Fahrenheit is important for maintaining the homeostasis in the body the body regular this temperature through the process called thermoregulation which involves brain skin muscle and other organ working together to maintain stable internal temperature
Stephanie
37A c
Wulku
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Diya Reply
anaemia is the decrease in RBC count hemoglobin count and PVC count
Eniola
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Diya Reply
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Diya
acid
Mary
I information on anatomy position and digestive system and there enzyme
Elisha Reply
anatomy of the female external genitalia
Muhammad Reply
Organ Systems Of The Human Body (Continued) Organ Systems Of The Human Body (Continued)
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what's lochia albra
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Source:  OpenStax, Xna game studio. OpenStax CNX. Feb 28, 2014 Download for free at https://legacy.cnx.org/content/col11634/1.6
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